Push-bar restrainers, or lock-out devices, are commonly known in the prior art. U.S. Pat. Nos. 1,357,007 and 2,212,957 and 3,722,938 and 4,331,354 are examples of the prior art showing mechanisms for holding the push-bar in the lock-out position. That is, devices are utilized for holding the push-bar down so that the door can be opened from the outside without any special key or the like.
The present invention improves upon the prior art in that it is a simplified but yet sturdy device which requires a special tool or key for releasing the device from its restraining position relative to the push-bar, and, there is only minimum amount of hardware on the door itself, so that one can normally depress the push-bar without fear of pinching one's fingers between the push-bar and the device.
The prior art devices permit themselves to be readily release from a restraining position, by anyone on the interior side of the door, so that the restrainer can be circumvented, since no special key or the like is required for releasing the device. Also, the prior art devices are commonly constructed of metal material which engages the push-bar and can therefore scratch and mar the bar, and the present invention avoids the aforementioned features.
Still further, the present device is arranged so that it can be readily adjusted to adapt to the dimensions of a particular door having a push-bar, and the adjustment can be made simply with a screwdriver and it can be made at the installation on the door itself.